A) $n = 5,\ l = 4,\ m = 0,\ s = + \frac{1}{2}$
B) $n = 3,\ l = 3,\ m = + 3,\ s = + \frac{1}{2}$
C) $n = 6,\ l = 0,\ m + 1,\ s = - \frac{1}{2}$
D) $n = 4,\ l = 2,\ m = + 2,\ s = 0$
Explanation
(a)
When, $n = 5,\ l = 0,\ 1,\ 2,\ 3\ or\ 4\ and\ m = - 4\ to + 4$
$\therefore n = 5,\ l = 4,\ m = 0,\ s = + \frac{1}{2}$ is a correct set of quantum numbers.